The invention relates to a torsion bar system for a vehicle axle, in particular a rear axle, of a two-track vehicle.
Such a torsion bar system is used in an active suspension control, in which a rotary actuator is assigned to each wheel suspension of the rear axle. Depending on activation, the two rotary actuators of the vehicle axle can be used to modify the ride height and/or to compensate pitch and roll movements of the vehicle.
DE 10 2009 005 895 A1 discloses a generic torsion bar system with a two-part stabilizer. The torsion bar system has a first rotary actuator and a second rotary actuator which are associated to vehicle sides, respectively. Each of the rotary actuators includes a motor-gear unit to generate the torques which are transmitted via a torsion bar and an output lever as actuating forces to a wheel suspension element of the vehicle axle. The motor-gear units of the two rotary actuators are arranged in a common housing which is mounted in fixed rotative engagement centrally to a cross member of a frame-shaped axle support or a subframe. The subframe, in turn, can be connected in a manner known per se to body-side longitudinal members of the vehicle body.
In particular when a driven rear axle is involved, a gear unit and/or an electric motor can be mounted between the longitudinal and transverse members of the subframe in driving relationship with the rear wheels via articulated shafts. During travel, such drive components introduce operating forces into the subframe. For reliably absorbing these operating forces, the subframe is of complex construction and incurs substantial material costs to realize sufficient structure stiffness.